From: Paul E. McKenney Date: Wed, 30 May 2012 00:50:51 +0000 (-0700) Subject: rcu: Make rcutorture fakewriters invoke rcu_barrier() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=72472a02a9c4507ef54d03d71bb253c26015f52c;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git rcu: Make rcutorture fakewriters invoke rcu_barrier() The current rcutorture rcu_barrier() testing never intentionally runs more than one instance of rcu_barrier() at a given time. This fails to test the the shiny new concurrency features of rcu_barrier(). This commit therefore modifies the rcutorture fakewriter kthread to randomly invoke rcu_barrier() rather than the usual synchronize_rcu(). Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 045a3dc233e..c279ee92094 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1025,7 +1025,11 @@ rcu_torture_fakewriter(void *arg) do { schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); udelay(rcu_random(&rand) & 0x3ff); - cur_ops->sync(); + if (cur_ops->cb_barrier != NULL && + rcu_random(&rand) % (nfakewriters * 8) == 0) + cur_ops->cb_barrier(); + else + cur_ops->sync(); rcu_stutter_wait("rcu_torture_fakewriter"); } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);